One of the principal purposes of Rousseau’s Discourse on Inequality is to distinguish between two forms of inequality: what he calls “natural” or “physical” inequality, and what he calls “contrived” or “artificial” or “moral” inequality. Natural inequality is the bucket into which Rousseau puts all of the characteristics that distinguish each of us “by nature”: our height, our natural intelligence, our handsomeness (or lack thereof), etc. Contrived inequality is everything else.

The two categories are not novel in of themselves; rather, what makes the argument of the Discourse provocative is how much inequality Rousseau says is contrived. He claims that natural inequality can explain basically none of the inequality that we see in society:

moral inequality, authorized by positive right alone, is contrary to natural right whenever it is not exactly proportioned to physical inequality—a distinction which sufficiently determines what ought to be thought in this regard of the sort of inequality that prevails among all civilized peoples, because it is manifestly contrary to the law of nature, however it may be defined, that a child command an old man, that an imbecile lead a wise man, and that a handful of people be glutted with superfluities while the starving multitude lacks necessities (117).

Rousseau’s distinction between two forms of inequality is, I think, one that appeals to many of our intuitions about inequality. When we seek to justify inequalities that we see in the world, we often appeal to the superior intelligence, or work ethic, or talent of the beneficiary of the inequality (consider any fawning profile of a Silicon Valley billionaire). Contrary to luck egalitarians — for better or worse — many of us seem to believe that there is no injustice is benefitting from our natural inheritance. Rousseau’s challenge is to the proportionality of differences that we find in the social world: we are sorely mistaken, he argues, about the degree of natural difference there is, and about whether or not those differences are reflected materially in the world around us.

While we may rationalize the distribution of status and goods on the basis of natural talents, natural inequality and contrived inequality are entwined in ways that make it difficult to isolate one or the other. When a wealthy student performs well on the SATs, that performance is the product both of some natural capacity as well as the many advantages that the student benefitted from growing up. Rousseau’s point is that those advantages (or disadvantages) are rarely, if ever, in proportion to our natural talents — that many of those advantages, in fact, are the perquisite of the talents or inheritance of others — e.g. our parents. Correspondingly, contrived inequality is almost always illegitimate (although one could imagine legitimizing disproportionate contrived inequality in the legitimate civil state of the Social Contract, perhaps). We mistakenly confuse one form of inequality for the other, and thereby authorize monstrous injustices.

Yet if this is the framework that many of us work through when considering inequality — and it is, after all, precisely this framework that leads e.g. to Nozick’s famous Wilt Chamberlain example — we seem to be on the cusp of technological change that will collapse in reality what we mistakenly do theoretically. If the advances being made in gene-editing progress to allow for the selection of advantageous traits like superior intelligence or athleticism, height or health, it is not hard to imagine the consolidation of contrived inequality — the often arbitrary product of convention — into natural inequality in one’s progeny. Because we already so thoroughly confuse the two, and often treat contrived inequality as the product of natural difference, perhaps it doesn’t matter in a practical sense. But if we are interested in such things, we would seem more than ever to need new intuitions about when and how inequality is authorized.